1. Field of the Invention
The present invention is directed to the manufacture of integrated circuit packages. More specifically, but without limitation thereto, the present invention is directed to optical proximity correction procedures for integrated circuit designs.
2. Description of the Prior Art
Optical Proximity Correction (OPC) is a step in the manufacturing process that semiconductor manufacturers employ to improve the quality of high-performance integrated circuit designs and to extend the lifetime of photolithography equipment. The overall lithography process involves projecting a circuit design from a mask through a complex lens system that forms the image of an integrated circuit design onto a wafer that will later be divided into individual chips. The resulting image of one of the masking layers, including metal layers and polysilicon layers, is used to construct the integrated circuit. The image contains critical dimensions that include line widths and spacing between adjacent features that may be smaller than the wavelength of the light used to image the mask on the wafer.